Thought I'd post again about wipers but a bit more useful than last time (instead of "HELP MY ALARMS GONE OFF AND WIPERS DON'T GO")... I know there a loads of threads on this, but I thought I'd add my findings and pictures anyway.
Today I cleaned out the P27 unit of grease, as best I could... I've attached some pictures. It all looks reasonably good really, the only thing is I'm not sure if it is possible to prise the lid off the black box without damaging it?
But I plugged it back in and it still doesn't work. There are some clicking noises coming from the black box, which is a good sign? And I measured 12V between pin B3 I think and ground, which is also a good sign.
So i'm thinking either the motor or the controller is dead?
I'll take it to uni tomorrow where I have a power supply that I can apply to the pins to see for sure.
Also, as an aside, if I press for washer fluid, the washer motor will stick on and will keep pumping until I turn off the ignition. Which is odd.
Workshop manual, windscreen wipers section:
Another useful wipers thread showing N14 relay unit: